U.S. Pat. No. 6,919,918 relates to an electronic digital door opener, comprising a digitalization, recording and control block that is connected between the street plate and the interior plates. Said block has sound recording, playback and processing means, video and data sequencing, in addition to means for controlling functions of the door opener. Each interior plate can be complemented with a remote control to enable audio and data communication with the street plate. Audiovisual and data communication with said plate can be enabled by means of a television set. A portable, mobile unit with television function enables audiovisual and data communication with the street plate either directly or by means of a television set. Each interior plate and the digitization, recording and control block may be connected to a remote localization module that makes it possible to relate audio, video and data communication and the controls of the door opener with a remote computer, remote telephone or the like.
US patent publication 20100148957 relates to a security system which includes a warning notification module adapted to recognize at least one of a wireless or audible signal. A door bell ringer or emergency transmission signal from a wireless transmitter can provide a recognition signal to a microprocessor in the security system via the warning notification module. The microprocessor retrieves dog barking sounds stored in memory and provides them to at least one of an amplifier or radio frequency transmitter after the microprocessor receives the recognition signal from the warning notification module. Dog barking sounds can be broadcasted using the wireless transmitter. Processing can be with a time delay after first receipt of the recognition signal. A random module can enable random retrieval of various dog barking sounds from memory for processing. A time out module can disable operation of the microprocessor at a set time after recognition signal receipt.
US patent publication 20090284600 relates to a remote-control door viewer surveillance system which includes a door viewer holding a lens assembly in the door panel of a house, an image sensor for picking up image signals through the lens assembly, an image processing circuit for processing image signals received from the image sensor into digital image signals, a monitor for displaying images of digital image signals outputted by the image processing circuit, a communication module for transmitting digital image signals outputted by the image processing circuit to the user's mobile phone, a memory for storing digital image signals outputted by the image processing circuit for further review, and a TCP/IP equipment for transmitting the digital image signal outputted by the image processing circuit to a computer at a predetermined IP address for monitoring and storage.
US patent publication 20090273670 relates to a remote viewing system for providing video surveillance of an entry or doorway of a building. A video camera is positioned to obtain video images of the entryway or doorway and to transmit them to a remote viewing station. Video data can be transmitted from the driver to any of a variety of electronic devices, including PCs, PDAs, cell phones, and the like. The video information can also be stored for future reference.
US patent publication 20080239072 relates to a door monitor with a portable storage medium includes a host module disposed behind the door, a night-vision camera module disposed outside the door and electrically connected with the host module, a sensor disposed outside the door for detecting whether any object is approaching, and a microphone connected with the host module. The host module has a multimedia processor, a display, a touch panel, and a portable storage medium connecting interface. The user enters monitoring criteria using the touch panel. When an object approaches and stays for a period of time, the night-vision camera module starts recording. The recorded video data are sent to and played on the display. The video data are compressed in a format and stored on the portable storage medium. The door monitor readily monitors situations outside the door and records and stores video images for the purposes of home security.